The present invention relates to a method for creating authenticated verifiable reproductions of electronic documents.
The multiplication of internet and computer networks has brought with it the emergence of numerous types of document formats and computer systems. As a result, users can access an increasingly large number of sources in order to gather information. It is therefore not uncommon for users to create electronic documents by reproducing or converting other documents from other file formats. This, however, presents some problems, primarily regarding the authenticity and accuracy of the reproduced or converted document. In short, there is no way that users can be certain that in the process of reproduction or conversion no unauthorized errors or changes were introduced to the data. Current technology has no capacity to allow for the authentication and verification of a reproduced or converted document in one format separately from the master document, which may be in another format.
An existing system, such as U.S. Pat. No. 4,933,969 to Marshall et al., is limited to the authentication and storage of data and protects against unauthorized modifications. While this type of data authentication system contributes greatly to ensuring the security and integrity of data, it does not address the authentication and verification of reproduced or converted documents from different electronic formats.
Other systems offer types of electronic functions that are related to the generation and authentication of electronic signatures. For example, U.S. Pat. No. 5,195,133 to Kapp et al. describes a system designed to generate a completed payment document, which can be signed by a customer, and then capture that customer""s signature in digital form. The principal feature of this mechanism is that it seeks to ensure that a signature approving a particular document was, in fact, captured at the time of the completion of the transaction to which it relates and was not obtained on some other occasion and merely reproduced for the particular transaction in question. The Kapp et al. patent creates a digital record of the transaction and captures a digital representation of the signature at the time the transaction is completed. This system then uses this digital record to encrypt the digital representation of the signature. However, this system is limited in that it does not apply to any situation where information may be reproduced or converted from an existing electronic document to another format and authenticated separately.
While each of the aforementioned systems can be useful for electronic business processes, they all have certain deficiencies. Current technology allows users to reproduce documents from one format to another. However, the above described systems lack the capacity to enable the user to authenticate and verify the reproduced documents separately from the master document.
It is an object of the present invention to provide a method for creating authenticated verifiable reproductions of electronic documents, in other words for ensuring that a translated document has not been altered from the original, master document. In accordance with the invention, this object is achieved with a method comprising the steps of:
(a) creating the electronic document under a first format;
(b) creating a document authentication code (DACm) linked to the electronic document;
(c) making the electronic document available to a user;
(d) for reproducing the document, performing the sub-steps of:
(i) opening the electronic document;
(ii) creating a DACmo linked to the opened electronic document;
(iii) retrieving DACm;
(iv) comparing DACm to DACmo and proceeding to the following sub-step only if DACm is equal to DACmo;
(v) reproducing the document in a format different from the first format to create a reproduced document;
(vi) creating a DACr for the reproduced document; and
(vii) linking DACm and DACr to the reproduced document.